Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1975_222_1_a1, author = {P. V. Berkhin}, title = {A selfadjoint boundary-value problem for the system $*du+\lambda u=f$}, journal = {Doklady Akademii Nauk}, pages = {15--17}, publisher = {mathdoc}, volume = {222}, number = {1}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1975_222_1_a1/} }
P. V. Berkhin. A selfadjoint boundary-value problem for the system $*du+\lambda u=f$. Doklady Akademii Nauk, Tome 222 (1975) no. 1, pp. 15-17. http://geodesic.mathdoc.fr/item/DAN_1975_222_1_a1/